European Cities 1M dataset

European Cities 1M dataset consists of 909,940 geo-tagged images from 22 European cities,
crawled from Flickr using geographic queries covering a window of each city center.
A subset of 1,081 images from Barcelona is annotated into 35 groups
depicting the same scene; 17 of the groups are landmark scenes and 18 are non-landmark.
Since not all scenes are landmarks, annotation cannot rely on tags; it is rather a combination
of visual query expansion and manual clean-up. Five images are selected as queries from each
group. If the group contains less than 5 images, all of them are used as a query (which is frequent for non-landmark scenes).
In total, we used 157 queries.

We have not included any other photos from Barcelona in the dataset, to ensure no other image
depicts the same scene/building as the ground truth. The remaining 908,859 images from the other 21 cities
are the distractors. Most of them depict urban scenery like the
ground-truth, making a challenging distractor dataset.

Contrary to our European Cities 50K dataset,
where the query images come from 9 European cities, here we chose all
query images from Barcelona. This is because, for this dataset,
we need to maximize the number of distractor images. For each city with query images we exclude from
the distractor dataset all other images except for the annotated ones. Therefore we pick queries from
just one city.

Sets of query images selected for evaluation for Landmark and Non-landmark scenes are depicted in
Figures 1 and 2 respectively, while sample images from the distractor set are presented in Figure 3.

Figure 1. Query images, one for each of the 17 landmark scenes in the annotated EC1M dataset.

Figure 2. Query images, one for each of the 18 non-landmark scenes in the annotated EC1M dataset.

Figure 3. Sample distractor images from the EC1M dataset.

Dataset Rights

The EC1M dataset consists of images downloaded from Flickr. Use of these images must respect the
corresponding terms of use.

Citation

Downloads

The annotated set of 1081 images is provided for downloading in two compressed files: the one contains the landmark scenes
and the other the non-landmark scenes. Images are in JPEG format with a maximum resolution of 500x500 pixels.
The 157 queries are a subset of the annotated set and their filenames are found in the corresponding text file below.
The set of 908K images used as distractors can be downloaded from Flickr using the
direct links provided in the compressed text file below. Frequently, some of the images are moved amongst
Flickr servers. We periodically update the list of URLs replacing broken links with the current
ones.